Traumatic brain injury (TBI) is a major cause of death and disability. In the United States alone approximately 1.4 million people sustain a TBI each year, of which 50,000 people die and over 200,000 are hospitalized. In addition, new research suggests that TBI is an independent significant risk factor of developing dementia and Alzheimer's disease. Despite the scientific and cost benefits of cross-study analyses, variability in measurement across studies has limited the ability to combine TBI data. To address this, the Federal Interagency TBI Research (FITBIR) Informatics System was developed as a platform to define, refine, and standardize data definitions for performing cross-study TBI research and as a central repository for phenotypic, genomic, and imaging data from TBI studies. The goal of this proposed work is to accelerate the process of building FITBIR into a large, rich database for meta- and secondary analysis of TBI clinical research data by archiving legacy data from the Citicoline Brain Injury Treatment Trial (COBRIT). COBRIT is a randomized, double-blind, placebo- controlled, multicenter trial studying the effects of 90 days of Citicoline on improving functional outcome in patients with complicated mild, moderate, and severe TBI. A comprehensive TBI assessment and drug test data were collected using 43 Case Report Forms (CRFs) in 16 modules containing more than 1,600 variables from approximately 1,200 patients over a 4 year period across eight clinical sites. The archiving of COBRIT in a standardized and harmonized format will help TBI investigators perform cross-study analyses about the natural history of TBI and the feasibility of new TBI therapeutics. Specifically, we will standardize and harmonize COBRIT variables using FITBIR Common Data Elements (CDEs) and Unique Data Elements (UDEs) by (1) assigning CDEs/UDEs to COBRIT variables that are Identical to FITBIR CDEs/UDEs; (2) defining and annotating COBRIT variables that are Comparable to FITBIR CDE/UDE; (3) defining and harmonizing COBRIT variables that are Related to FITBIR CDE/UDEs; and (4) Creating new data elements for COBRIT variables not found in FITBIR CDEs/UDEs. Next, we will contribute the standardized and harmonized COBRIT data to FITBIR by (1) generating FITBIR Global Unique Identifiers (GUID) for COBRIT subjects; (2) validating data formats using the FITBIR Data Validation Tool; and (3) submitting standardized and harmonized COBRIT data using the FITBIR Upload Tool.